Trough pan for a face conveyor with a loading ramp

ABSTRACT

A conveyor pan  10  for face conveyors in underground coal mining systems has outward race  1  and return race  2 , between which a conveyor bottom  9  is formed, with toggle sockets  21 , with guide means for a mining machine which can be moved along the wall, in particular a drum cutter-loader, and with a static loading ramp connected on the wall side to the conveyor pan, and extending from the floor to the level of the outward race, by means of which muck can be loaded into the outward race as the face conveyor is advanced. The loading ramp includes an angled guide plate  50 , the lower section  51  of which is steeper relative to the conveyor bottom  9  or the floor  11  than the upper section  52.

The invention relates to a conveyor pan for face conveyors inunderground winning systems, in particular coal winning systems, withoutward race and return race for guiding a scraper chain, between whicha conveyor bottom is formed, with securing means attached to the ends ofthe conveyor pans on the goaf side and the wall side for a connectingcomponent linking adjacent conveyor pans traction-proof together,preferably with guide means for a mining machine which may be movedalong the wall and with a static loading ramp connected to the conveyorpan on the wall side and extending from the floor to the level of theoutward race, by means of which muck may be loaded into the outward raceas the face conveyor is advanced.

Conveyor pans for face conveyors are known in various embodiments. Inunderground workings in which the mining machine travels along the wall,as for example in workings using a plow, the muck can be loaded into theoutward race of the face conveyor by means of special devices or guideplates on the mining machine. Conveyor pans with static loading rampsare used in particular in mining systems which operate using travelingmining machines, moving along between the conveyor and the wall, whichhave stationary mining machines, for example attached to the poweredsupport assembly (DE 197 36 662), or which are designed as guides fordrum cutter-loaders. In this type of workings with drum cutter-loadersthe guide means on the wall side, for example a sliding rail or trackfor the drum cutter-loader, may simultaneously also form the lowersection of the face conveyor loading ramp (DE 197 20 536).

Within face support systems, the conveyor pans connected together toform a face conveyor are advanced by means of the booms or pushersabutting the powered shield support frames. During advancing, theconveyor pans of the face conveyor tend to climb, in other words to riseup off the floor, and this disadvantageous climbing has to be counteredwith suitable control measures for adjusting the cutting horizon.Climbing of the face conveyor is particularly disadvantageous when, asin the case of drum cutter-loaders, the mining machine is guided alongthe face conveyor.

Object of the present invention is to minimize the disadvantageousclimbing of a face conveyor by constructional measures on the conveyorpan.

This object is fulfilled by means of the invention as recited in claim1. In accordance with the present invention the loading ramp consists ofa curved or, in particular, an angled guide plate, the lower section ofwhich is steeper relative to the floor or relative to the bottom of thechannel than its upper section. Static loading ramps in the prior artconsisted of modular components which on the wall side were attached tothe side walls or side sections of the conveyor pans and a ramp whichwas flat for the entire extent of the conveyor pan, i.e. was disposed ina wedge-shaped position relative to the wall or to the floor or,alternatively, had a curved ramp with a relatively flat lower section,becoming steeper towards the outward race, and thus being curved towardsthe wall. The applicant has determined that by attachment of a wall-sideguide plate and modification of the contour of the guide plate into acurve away from the wall the climbing tendency of the face conveyorduring advancing is reduced. The curve entails in particular bending theguide plate such that its lower section is steeper. By means of thesemeasures the static loading ramp is kept relatively short overall andincreases the overall weight of the conveyor pan only slightly.

In the embodiment of the conveyor pan preferred by the applicant theapex line of the curve or the apex line of the bend of the guide platemay be disposed at the level of the conveyor bottom, preferably betweenthe middle and the underside of the conveyor bottom and/or positionedbelow the center line of the point of application of force to theconveyor pan by the booms or pushers abbutting the support system, andconsequently below the articulation point of the advancing systemdisposed on the goaf side for moving the face conveyor. A particularlypreferred variant has a guide plate with sections angled relative toeach other, with the lower and the upper section both being essentiallyflat and enclosing an angle of approximately 150°-170°, preferablyapproximately 160° ±4°. It is also advantageous if the lower section isangled by approximately 65°-85°, preferably 78°±4°, relative to theconveyor bottom and the upper section is angled by approximately45°-65°, preferably 55°±4°, relative to the conveyor bottom.

For the assembly and disassembly of the face conveyor and for exchangeof individual conveyor pans it is advantageous if the guide plate isfitted at the ends of the conveyor pan with recesses, which are matchedin size to the dimensions of the securing means and/or conveyor panconnecting components. The securing means on the conveyor pan preferablyconsist of toggle bolt sockets and the conveyor pan connectingcomponents preferably consist of toggle bolts, the heads of which can beinserted in the sockets. The recess may in particular be formed suchthat the lower section of the guide plate has or forms a bar at thelower edge, this bar extending as far as both conveyor pan ends, so thatthe guide plate at its lower edge is fully in contact with the conveyorpan's sheet metal bottom or similar and only has recesses at therespective conveyor pan ends, into which slack and fines can enter.Since after a short period of operation of the face conveyor theserecesses clog up, the loading performance of the static loading ramp isnot impacted by the recesses and the conveyor pan in accordance with thepresent invention retains its lesser degree of disadvantageous climbingby comparison with generic conveyor pans. The limiting wall of therecess, which runs essentially parallel to the conveyor pan ends andcontinues as far as the level of the outward race, is preferablyequipped with a detent, so that on the one hand sufficient clearance isprovided to insert/remove the heads of the toggles, and on the otherhand by means of the detent a type of cutout is created, thus giving, atthe transition point from the guide plate to the recess, a betterdirection of the forces to be absorbed into the connected or welded-onarea of the conveyor pan.

In a preferred embodiment the guide plate is welded to the conveyor pan.This is particularly advantageous if the lower section of the guideplate, in particular the bar at its lower edge, is welded to a bottombar on the wall side, to a sliding bar or to a machinery guide for themining machine. By means of the weld seam at the lower edge and theconnection with a bottom bar or sliding bar the layers of muck disposedon the floor are forced upwards over the entire width of the conveyorpan as the conveyor is advanced, without its being possible for coal orsimilar in this area to penetrate behind the guide plate and causedisadvantageous climbing of the conveyor.

The guide plate in accordance with the present invention may be usedboth with conveyor pans having lower race and outward race permanentlyattached to each other and with conveyor pans having a removable troughas the outward race. With the permanently attached outward race, theside section may consist of rolled steel sections and comprise anapproximately T-shaped cross-section, as is known for example from DE 4006 183 A1, rendering it possible for the upper section of the guideplate to be welded to the underside of the horizontal web of theL-shaped or T-shaped side section. With conveyor pans having a removabletrough as the outward race the upper section of the guide plate ispreferably welded to the framework holding the removable trough.

Since considerable forces are applied to the guide plate when the faceconveyor is advanced and when muck is loaded into the outward race, itis preferable if at least two support plates are disposed between theguide plate and the side wall on the wall side and/or the side sectionsof the outward race and/or return race. This also makes it possible tokeep the thickness of the guide plate relatively low. It is beneficialif the guide plate then features vertical slots at the level of thesupport plates, so that additional weld seams can be located in theslots, thus connecting the guide plate to the conveyor pan. The guideplate may be equipped with a hole for the hook of a lifting device,either between the slotted recesses and/or in the center.

The preferred application of the conveyor pans in accordance with thepresent invention is with face conveyors having guide means for acutting mining machine, in particular having guide means for a drumcutter-loader. In the case of a conveyor pan having guide means for adrum cutter-loader the tendency to climb can be further minimized if thehorizontal web of the outward race's side section on the wall sidesimultaneously forms the wall-side guide for the drum cutter-loader andthe drum cutter-loader then runs on that horizontal web. These measuresalso allow the mining machine to be kept more compact, so that the roofshield over the shield supports can also be kept shorter than withconveyor pans featuring on the wall side a separate machine track aheadof the wall-side side section of the conveyor pans.

Further advantages and embodiments of the conveyor pan in accordancewith the present invention will be found in the following description ofan exemplary embodiment represented in the drawing. In the drawing:

FIG. 1 shows a perspective view of a conveyor pan in accordance with thepresent invention with a guide plate welded on the wall side as theloading ramp; and

FIG. 2 shows a partial cross-sectional view along line II-II in FIG. 1.

Conveyor pan 10 shown in perspective in FIG. 1 is used, for example, oncenter-chain or double center-chain scraper conveyors, on which thesingle or double scraper chain is guided approximately in the middle ofthe conveying trough and on which the ends of the scrapers are guided inguide channels, formed in upper outward race 1 and in return race orlower race 2 and, for example, limited by means of T-shaped sidesections 3, 4, 5, 6. A face conveyor is then formed in the normal mannerfrom individual conveyor pans 10. The longitudinal side 7 of the faceconveyor, shown in the rear of FIG. 1, is disposed on the goaf side,while the longitudinal side 8, shown in the front of FIG. 1, is alignedparallel to the wall in the underground face, not shown. Between outwardrace 1 and lower race 2 is a conveyor bottom 9, to which are welded—inthe exemplary embodiment shown—all side sections 3, 4, 5, 6 with theirsupports 13, 14, 15, 16 facing conveyor bottom 9 and matched to theshape of the scrapers, not shown. In the exemplary embodiment shown, allside sections 3 to 6 are identical and consist of rolled steel sectionsof an essentially T-shaped cross-section, with the supports 13, 14, 15,16, matched in shape to the scraper ends, forming the “stalk” of the Tand transitioning into a horizontal web 17, 18, 23, 24. Both on the goafside and on the wall side, toggle sockets 21 or 22 are welded in thevicinity, respectively, of the conveyor pan ends 19 or 20 formed by thetransverse sides, into which the toggle heads of toggle bolts engage inthe normal manner, in order to join together adjacent conveyor pans 10such that they are resistant to traction but have a slight permissiblehorizontal and vertical angular movement. The toggle sockets on the goafside and the toggle bolts are not shown. A bottom plate 25 is welded inplace below horizontal webs 23, 24 of the side sections 5, 6 of lowerrace 2. FIG. 1 also shows that, as is already known, conveyor bottom 9is fitted at both conveyor pan ends 19, 20 with overlapping sectionsshaped to match each other.

In accordance with the present invention conveyor pan 10 comprises onthe wall side 8 a static loading ramp for muck from loosened rock, inparticular loosened coal, consisting of the guide plate identified inits entirety as 50, welded to conveyor pan 10 and extending from floor11 (FIG. 2) up to the level of outward race 1. Guide plate 50 comprisesa lower section 51 and an upper section 52, which are each essentiallyflat and are angled relative to each other at the apex line 53. In thearea of the two toggle sockets 21, 22 guide plate 50 is fitted withrecesses 54, 55, extending over the entire height of upper section 52and over approximately half the height of lower section 51. The scaleand dimensions of recesses 54, 55 on guide plate 50 are matched to thescale and dimensions of toggle sockets 21, 22 and to those of the togglebolts, not shown, that can be engaged in the latter. Lower edge 56 ofguide plate's 50 lower section 51 extends over the entire width of theconveyor pan, so that guide plate 50 forms a narrow bar 60 extendingover the entire width of the conveyor pan, in order to direct the mucktowards outward race 1 as the face conveyor is advanced. The lower edgeof the bar 60 is welded to a sliding bar 26 by means of a weld seam (57,FIG. 2), with the sliding bar being welded below the horizontal web 24of the lower side section 6 on the wall side. The sliding bar extendsbeyond the side wall of conveyor pan 10 formed by the outer faces ofside sections 3, 6 and conveyor bottom 9, on the wall side. Bar 60 formsthe lower limiting wall of recesses 54, 55 while the essentiallyvertical limiting wall 54′, 55′ of recesses 54, 55 is fittedapproximately at the level of apex line 53 with a detent 62 or 63. As aresult of detent 62, 63 the upper section 52 of the guide platestransitions in a curve into the conveyor pan. Detents 62, 63 and thecurved shape reduce the danger of formation of fracture cracks in sidesection 3.

As FIG. 2 shows clearly, sliding bar 26 is slightly angled relative tothe conveyor bottom or to sheet metal bottom 25 by approximately 5°, sothat conveyor pan 10 is in contact with floor 11 in the underground faceonly in the frontal area 27 of the underside of sliding bar 26. FIG. 2also shows in particular that guide plate 50 forming the loading rampincludes an angle α of approximately 160° between lower section 51 andupper section 52 and that lower section 51 of guide plate 50 is steeperrelative to floor 11 or to conveyor bottom 9 than upper section 52. Thebend of the lower, essentially flat section 51 of guide plate 50relative to conveyor bottom 9 is shown in FIG. 2 as β and isapproximately 78°±4°, while the angle γ of upper section 52 to conveyorbottom 9 is approximately 55°±4°. As a result of this differing slope oflower section 51 and upper section 52 and the overall extremely steepshape of loading ramp 50 between the wall-side front face 28 of slidingbar 26 and the front face 29 of horizontal web 17 of the outward race'sside section 3, the conveyor pan in accordance with the presentinvention is made considerably shorter than was the case with knownconveyor pans.

Between guide plate 50 and the outer faces of side sections 3, 6 supportplates 30 are disposed, with the wall-side edge 31 being matched to thecontour of the bend of guide plate 50. Support plates 30 are welded toside sections 3, 6 and if appropriate also to conveyor bottom 9, andguide plate 50 features, as shown in FIG. 1, two vertical slots 58, 59,which run level with and parallel to support plates 30, 32, in orderthat weld seams in vertical slots 58, 59 may give additionalreinforcement between guide plate 50 and support plates 30, 32. Betweenvertical slots 58, 59 a hook hole 61 is formed, being located in thecenter of guide plate 50 and being vertically disposed.

The representation of conveyor pan 10 does not show the guide means fora mining machine. In the preferred application of the conveyor pans amounting shaft with, for example, a drive rack for a drum cutter-loaderis mounted on the goaf side and the upper face 17′ of the horizontal web17 of the wall-side side section 3 of outward race 1 forms a track forthe drum cutter-loader.

The person skilled in the art can deduce from the preceding descriptiona series of modifications which are also intended to fall within theprotection of the dependent claims. In one embodiment, not shown, withremovable trough the upper edge of the guide plate is welded to theframe construction for supporting and fixing the removable trough. Inaddition, ahead of the angled guide plate forming the static loadingramp a section of a machine track could also be formed. Instead of anangled guide plate with flat sections the guide plate could also berounded or curved, within limits, and the apex line could also belocated higher than the conveyor bottom. The securing means and conveyorpan-joining components could be different from the toggle sockets andmatching toggle bolts shown, which would also cause the shape of therecesses to be different.

1. A conveyor pan for face conveyors in underground mining systems, inparticular coal minings systems, with outward race and return race toguide a scraper chain, between which a conveyor bottom is disposed, withon the goaf side and on the wall side securing means located at theconveyor pan ends for a connecting component to link adjacent conveyorpans together, with guide means for a mining machine which may be movedalong the wall and with a static loading ramp connected to the conveyorpan on the wall side and extending from the floor to the level of theoutward race, by means of which muck may be loaded into the outward raceas the face conveyor is advanced, said loading ramp comprising a curvedor angled guide plate, a lower section of which is steeper relative toan associated floor or to the conveyor bottom than an upper sectionthereof.
 2. The conveyor pan of claim 1, wherein an apex line of theguide plate is disposed at the level of the conveyor bottom.
 3. Theconveyor pan of claim 1, wherein an apex line of the guide plate islocated below an articulation point of an advancing system or pusherbeams disposed on the goaf side for moving the face conveyor.
 4. Theconveyor pan of claim 1, wherein the lower section and the upper sectionof said angled guide plate are generally flat and include an angle ofapproximately 150°-170°.
 5. The conveyor pan of claim 1, wherein thelower section is inclined relative to the conveyor bottom by an angle ofapproximately 65°-85°and the upper section is inclined relative to theconveyor bottom by an angle of approximately 45°-65°.
 6. The conveyorpan of claim 1, wherein the guide plate is equipped at conveyor pan endswith recesses sized to match dimensions of at least one of the securingmeans and the conveyor pan-connecting component.
 7. The conveyor pan ofclaim 1, wherein the securing means includes toggle bolt sockets and theconveyor pan-connecting components includes toggle bolts, the toggleheads are engageable in the toggle bolt sockets.
 8. The conveyor pan ofclaim 1, wherein the lower section of the guide plate forms a bar at alower edge thereof, which extends as far as pan ends of the conveyorpan.
 9. The conveyor pan of claim 6, wherein a limiting wall of one ofthe recesses includes a detent parallel to pan ends of the conveyor pan.10. The conveyor pan as recited in one of claim 1, wherein the guideplate is welded to the conveyor pan.
 11. The conveyor pan as recited inone of claim 1, wherein the lower section of the guide plate, is weldedto a sliding bar on the wall side or to a machinery guide for the miningmachine.
 12. The conveyor pan of claim 1, wherein the upper section ofthe guide plate is welded to an underside or front face of a horizontalweb of an approximately T-shaped or L-shaped rolled steel side section.13. The conveyor pan of claim 1, wherein the conveyor pan includes aremovable trough as the outward race and the upper section of the guideplate are welded to the frame holding the removable trough.
 14. Theconveyor pan as recited in one of claim 1, wherein in a center area ofthe guide plate a hole for a lifting hook is defined.
 15. The conveyorpan of claim 1, wherein at least two support plates are disposed betweenthe guide plate and at least one of the side wall on the wall side, theside sections of the outward race, and the return race.
 16. The conveyorpan of claim 15, wherein the guide plate has vertical slots at the levelof the support plates.
 17. The conveyor pan of claim 1, wherein guidemeans for a cutting mining machine are included with the horizontal webof the outward race side section on the wall side.
 18. A loading rampfor a conveyor pan of an underground mining face conveyor, said loadingramp comprising: a guide plate having a lower section and an uppersection formed integrally therewith, said lower section angled steeperthan said upper section relative to one of a bottom of an associatedconvey pan and an associated support surface.
 19. The loading ramp ofclaim 18 wherein an apex between said lower section and said uppersection is positioned at approximately the same height as said bottom ofsaid associated conveyor pan.
 20. A conveyor pan for a face conveyorused in underground mining systems, said conveyor pan comprising: aconveyor bottom disposed between an outward race and a return race forguiding a scraper chain; a securing means disposed on opposed ends ofsaid conveyor bottom for engagement with an associated connectingcomponent for linking adjacent conveyor pans together; and a loadingramp connected to said conveyor bottom on a wall side thereof forloading much into said outward race, said loading ramp extending from anunderlying support surface to said outward race and including: a curvedor angled guide plate having a lower section and un upper section, saidlower section positioned at a greater angle relative to said supportsurface than said upper section.